Crystal growth and characterization of LixLa(1−x)/3NbO3 using Czochralski method

Single crystals of LixLa(1−x)/3NbO3 were grown in air using Czochralski method from La-poor melt. The lithium-ion conductivity of the crystals was measured. The length and maximum diameter of the boule grown were 23 and 20 mm, respectively. The boule contained no inclusions but was covered with a very thin polycrystalline film of LaNbO4 and LiNbO3 in its upper region. The composition of the crystals grown was estimated to be x = 0.15 and the starting melt composition was x = 0.20. The ionic conductivity of the crystal was anisotropic with σ[100] = 2.8 × 10−4 S cm−1 and σ[001] = 9.7 × 10−5 S cm−1 at 306 K. The activation energy, Ea of these conductivities was almost the same in the range of 0.28–0.29 eV. Further, we discussed the anisotropic lithium-ion conductivity of the crystal.